U.S. researchers say they've developed a sampling system that can collect particles from shoes and suck them away for analysis in airport security gates. The technology could lead to efficient and unobtrusive screening for trace amounts of explosives on airline passengers without causing frustration among inconvenienced fliers, a release from the American Institute of Physics said Monday. Researchers at the National Institute of Standards and Technology said they've developed several different versions of the system. "One particular device is a kiosk-style instrument that people step into, never having to physically remove their shoes for sampling," NIST engineer Matthew Staymates said. "Air jets are located in strategic locations and used to dislodge particles from the shoe surface, and a large blower establishes a bulk flow field that ensures all liberated particles are transported in the appropriate direction." For commercial use, the sampling system, which can collect particles in just 6 to 7 seconds, would have to be combined with a particle collection device and a chemical analyzer, Staymates said. "Incorporating a particle collection device and chemical analyzer would certainly be possible in the current prototype, but it was outside of the scope of the project," he said. "NIST's role was to uncover the fundamental connection between fluid dynamics and trace aerodynamic sampling, and use our findings to help in the development of next-generation sampling approaches."